How to diagnose cabin fan problems.

Hi all.

I've got a 1st gen 4x4 1st gen extended cab Tacoma with over 400,000 miles. Its been a bit of a challenge lately keeping this old girl on the road!

Last night, the cabin fan quit working. I was wondering if anyone had tips on troubleshooting. Summer heat is no fun without some A/C.

What I've done so far:
1. Checked fuses. Nothing was labeled "Fan" but I did check the A/C fuse and it looked fine
2. When I turned the fan on, I can hear/feel the alternator dragging the engine at idle, meaning it must be drawing power.

Any other tips/suggestions? I can live without a fan for a while, but I can't really afford to take this truck to a mechanic, and I especially can't go through winter without heat here in Colorado!

Thanks a bunch!

 

1. Fan speed control switch?
2. I'm not sure if there might be some kind of resister on the fan that could be bad?

Here is a thread to look into as well....


https://www.tacomaworld.com/threads/fan-speed-switch-not-working.70275/page-3

 

|Fan speed control swith?
I've tried it at all speeds, nothing seems to work.

Thanks for the thread link! I'll have to figure out where the blower motor is actually located under my dash.

 

|Under the glove box..

So, thanks to that tip, I was able to remove the blower motor. Simple job, three screws. I'm not sure how the wiring comes loose, but after knocking it around a bit, the motor started working, so I just put it back. I'm sure it's just a corroded connection.

Not sure how to correct or clean the corrosion since the wiring looks "permanent" to me. I could rip it out of course, but I think it would just make matters worse. Oh well, everything is working fine for now..

 

replacement fans aren't terribly expensive (30ish dollars). mine shook the whole dash when i got my truck. i opened it up and found a mummified mouse in there.

if you have to replace it...well, you already know how easy it is to get it in and out!

 

I was ready to replace my blower motor a year ago. It wouldn't always come on. If I reached under the glove box and tapped it, it would start. Then it just started working 100% again (about a year ago).

 

There is a plug the blower motor just plugs into the harness

 

if you start seeing intermittent functionality on HIGH only, then most likely your resistor - check this, see PDF
https://www.tacomaworld.com/threads/blower-motor-resistor-location-2001-tacoma.266540/#post-6541131

 

I have noticed my blower only working on high for the past month or so, and TacomaWorld comes to the rescue once again!

1. Take out two philips head screws to remove the glove box. Unplug 4-prong harness.
2. Test resistance against factory specs (see post above mine) using a digital multi-meter I use for work. Pins 1-4 tested Good. Pins 1-3 and 1-2 failed the resistance test.
3. Take out two philips head screws to remove the blower motor resistor.
4. Visual inspection confirms. Corrosion on the exposed brass between the plate and the ceramic block.
5. Called up Camelback Toyota and ordered a new one PN# 87138-35040 it's only $10.49, cheaper than Amazon. (Edit: Parts guy mentions Toyota has an upgraded pigtail connector to prevent issues they've had with burnt pins. Turns out, this is only an issue on the 2nd Gen. 2005 and newer models. PN#
   $32 82141-04M40
   82141-04M40.)
6. Parts will be in tomorrow, but it's as simple as plugging them in and re-installing the 4 screws. Thanks to knowing the resistance specs, I am certain this will fix the problem. Edit: I got the new part and tested the resistance across each set of prongs. The new resistor did not pass the test on 1-3, it only gave me 0.7 Ohms. I'm going to take it back to the dealership and get a replacement. I tried plugging it in and fan setting 3 blew too low.

This is a 10 minute fix. I am truly grateful to all of you for the wealth of information available on TW.